447 research outputs found

    Chronopotentiometric study of the transport of phosphoric acid anions through an anion-exchange membrane under different pH values

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    [EN] Phosphate is the main cause of eutrophication in many water bodies. Its presence in waters is associated to the fact that is not completely removed in conventional wastewater treatment plants. On the other side, phosphate rocks are a non-renewable resource and considered as a critical raw material. A membrane separation process, able to recover phosphate from wastewater, is a promising process to avoid pollution and to reuse phosphate. This paper investigates the transport of salts of phosphoric acid through an anion-exchange membrane (AEM) by means of chronopotentiograms and polarization curves (CVCs). The presence of multiple transition times in the chronopotentiograms and the corresponding limiting current densities in the CVCs indicate a change in the species being transported in the membrane/diffusion boundary layer system, due to the hydrolysis reactions that take place when the concentration polarization is reached. Under the experimental conditions tested, coupled convection (gravitational and elctroconvection) occurs when a certain threshold in the membrane voltage drop is surpassed independently of the electrolyte concentration. However, at high pH values, only one transition time in the chronopotentiograms, due to the transfer of OH- ions with greater concentration and mobility. This fact is reflected in the CVCs by the large plateaus obtained, which hinders the occurrence of coupled convection phenomena, and consequently, water splitting can be considered as the main mechanism responsible for the overlimiting regime.The authors wish to thank the financial support from FINEP, FAPERGS, CAPES and CNPq (Brazil), from the BRICS-STI/CNPq (BRICS STI Framework Programme), from the European Union through the Erasmus Mundus Program (EBW +) and from the CYTED (Network 318RT0551).Gally, C.; García Gabaldón, M.; Ortega Navarro, EM.; Bernardes, A.; Pérez-Herranz, V. (2020). Chronopotentiometric study of the transport of phosphoric acid anions through an anion-exchange membrane under different pH values. Separation and Purification Technology. 238:1-10. https://doi.org/10.1016/j.seppur.2019.116421S110238Cordell, D., Drangert, J.-O., & White, S. (2009). The story of phosphorus: Global food security and food for thought. Global Environmental Change, 19(2), 292-305. doi:10.1016/j.gloenvcha.2008.10.009Cordell, D., Rosemarin, A., Schröder, J. J., & Smit, A. L. (2011). Towards global phosphorus security: A systems framework for phosphorus recovery and reuse options. Chemosphere, 84(6), 747-758. doi:10.1016/j.chemosphere.2011.02.032Van Vuuren, D. P., Bouwman, A. F., & Beusen, A. H. W. (2010). Phosphorus demand for the 1970–2100 period: A scenario analysis of resource depletion. Global Environmental Change, 20(3), 428-439. doi:10.1016/j.gloenvcha.2010.04.004Gilbert, N. (2009). Environment: The disappearing nutrient. Nature, 461(7265), 716-718. doi:10.1038/461716aHao, X., Wang, C., van Loosdrecht, M. C. M., & Hu, Y. (2013). Looking Beyond Struvite for P-Recovery. Environmental Science & Technology, 47(10), 4965-4966. doi:10.1021/es401140sArnaldos, M., & Pagilla, K. (2010). Effluent dissolved organic nitrogen and dissolved phosphorus removal by enhanced coagulation and microfiltration. Water Research, 44(18), 5306-5315. doi:10.1016/j.watres.2010.06.066Babatunde, A. O., & Zhao, Y. Q. (2010). Equilibrium and kinetic analysis of phosphorus adsorption from aqueous solution using waste alum sludge. Journal of Hazardous Materials, 184(1-3), 746-752. doi:10.1016/j.jhazmat.2010.08.102Kralchevska, R. P., Prucek, R., Kolařík, J., Tuček, J., Machala, L., Filip, J., … Zbořil, R. (2016). Remarkable efficiency of phosphate removal: Ferrate(VI)-induced in situ sorption on core-shell nanoparticles. Water Research, 103, 83-91. doi:10.1016/j.watres.2016.07.021Maher, C., Neethling, J. B., Murthy, S., & Pagilla, K. (2015). Kinetics and capacities of phosphorus sorption to tertiary stage wastewater alum solids, and process implications for achieving low-level phosphorus effluents. Water Research, 85, 226-234. doi:10.1016/j.watres.2015.08.025Furuya, K., Hafuka, A., Kuroiwa, M., Satoh, H., Watanabe, Y., & Yamamura, H. (2017). Development of novel polysulfone membranes with embedded zirconium sulfate-surfactant micelle mesostructure for phosphate recovery from water through membrane filtration. Water Research, 124, 521-526. doi:10.1016/j.watres.2017.08.005Zhang, Y., Desmidt, E., Van Looveren, A., Pinoy, L., Meesschaert, B., & Van der Bruggen, B. (2013). Phosphate Separation and Recovery from Wastewater by Novel Electrodialysis. Environmental Science & Technology, 47(11), 5888-5895. doi:10.1021/es4004476Valverde-Pérez, B., Wágner, D. S., Lóránt, B., Gülay, A., Smets, B. F., & Plósz, B. G. (2016). Short-sludge age EBPR process – Microbial and biochemical process characterisation during reactor start-up and operation. Water Research, 104, 320-329. doi:10.1016/j.watres.2016.08.026Chen, X., Zhou, H., Zuo, K., Zhou, Y., Wang, Q., Sun, D., … Huang, X. (2017). Self-sustaining advanced wastewater purification and simultaneous in situ nutrient recovery in a novel bioelectrochemical system. Chemical Engineering Journal, 330, 692-697. doi:10.1016/j.cej.2017.07.130Le Corre, K. S., Valsami-Jones, E., Hobbs, P., & Parsons, S. A. (2009). Phosphorus Recovery from Wastewater by Struvite Crystallization: A Review. Critical Reviews in Environmental Science and Technology, 39(6), 433-477. doi:10.1080/10643380701640573Ueno, Y., & Fujii, M. (2001). Three Years Experience of Operating and Selling Recovered Struvite from Full-Scale Plant. Environmental Technology, 22(11), 1373-1381. doi:10.1080/09593332208618196Battistoni, P., Boccadoro, R., Fatone, F., & Pavan, P. (2005). Auto-Nucleation and Crystal Growth of Struvite in a Demonstrative Fluidized Bed Reactor (FBR). Environmental Technology, 26(9), 975-982. doi:10.1080/09593332608618486Liu, R., Wang, Y., Wu, G., Luo, J., & Wang, S. (2017). Development of a selective electrodialysis for nutrient recovery and desalination during secondary effluent treatment. Chemical Engineering Journal, 322, 224-233. doi:10.1016/j.cej.2017.03.149Ren, S., Li, M., Sun, J., Bian, Y., Zuo, K., Zhang, X., … Huang, X. (2017). A novel electrochemical reactor for nitrogen and phosphorus recovery from domestic wastewater. Frontiers of Environmental Science & Engineering, 11(4). doi:10.1007/s11783-017-0983-xWimalasiri, Y., Mossad, M., & Zou, L. (2015). Thermodynamics and kinetics of adsorption of ammonium ions by graphene laminate electrodes in capacitive deionization. Desalination, 357, 178-188. doi:10.1016/j.desal.2014.11.015Huang, G.-H., Chen, T.-C., Hsu, S.-F., Huang, Y.-H., & Chuang, S.-H. (2013). Capacitive deionization (CDI) for removal of phosphate from aqueous solution. Desalination and Water Treatment, 52(4-6), 759-765. doi:10.1080/19443994.2013.826331Wang, X., Wang, Y., Zhang, X., Feng, H., Li, C., & Xu, T. (2013). Phosphate Recovery from Excess Sludge by Conventional Electrodialysis (CED) and Electrodialysis with Bipolar Membranes (EDBM). Industrial & Engineering Chemistry Research, 52(45), 15896-15904. doi:10.1021/ie4014088Ebbers, B., Ottosen, L. M., & Jensen, P. E. (2015). Electrodialytic treatment of municipal wastewater and sludge for the removal of heavy metals and recovery of phosphorus. Electrochimica Acta, 181, 90-99. doi:10.1016/j.electacta.2015.04.097Pismenskaya, N., Nikonenko, V., Auclair, B., & Pourcelly, G. (2001). Transport of weak-electrolyte anions through anion exchange membranes. Journal of Membrane Science, 189(1), 129-140. doi:10.1016/s0376-7388(01)00405-7Belashova, E. D., Kharchenko, O. A., Sarapulova, V. V., Nikonenko, V. V., & Pismenskaya, N. D. (2017). Effect of Protolysis Reactions on the Shape of Chronopotentiograms of a Homogeneous Anion-Exchange Membrane in NaH2PO4 Solution. Petroleum Chemistry, 57(13), 1207-1218. doi:10.1134/s0965544117130035Belashova, E. D., Pismenskaya, N. D., Nikonenko, V. V., Sistat, P., & Pourcelly, G. (2017). Current-voltage characteristic of anion-exchange membrane in monosodium phosphate solution. Modelling and experiment. Journal of Membrane Science, 542, 177-185. doi:10.1016/j.memsci.2017.08.002Melnikova, E. D., Pismenskaya, N. D., Bazinet, L., Mikhaylin, S., & Nikonenko, V. V. (2018). Effect of ampholyte nature on current-voltage characteristic of anion-exchange membrane. Electrochimica Acta, 285, 185-191. doi:10.1016/j.electacta.2018.07.186Paltrinieri, L., Poltorak, L., Chu, L., Puts, T., van Baak, W., Sudhölter, E. J. R., & de Smet, L. C. P. M. (2018). Hybrid polyelectrolyte-anion exchange membrane and its interaction with phosphate. Reactive and Functional Polymers, 133, 126-135. doi:10.1016/j.reactfunctpolym.2018.10.005Rybalkina, O., Tsygurina, K., Melnikova, E., Mareev, S., Moroz, I., Nikonenko, V., & Pismenskaya, N. (2019). Partial Fluxes of Phosphoric Acid Anions through Anion-Exchange Membranes in the Course of NaH2PO4 Solution Electrodialysis. International Journal of Molecular Sciences, 20(14), 3593. doi:10.3390/ijms20143593Martí-Calatayud, M. C., Buzzi, D. C., García-Gabaldón, M., Bernardes, A. M., Tenório, J. A. S., & Pérez-Herranz, V. (2014). Ion transport through homogeneous and heterogeneous ion-exchange membranes in single salt and multicomponent electrolyte solutions. Journal of Membrane Science, 466, 45-57. doi:10.1016/j.memsci.2014.04.033Benvenuti, T., García-Gabaldón, M., Ortega, E. M., Rodrigues, M. A. S., Bernardes, A. M., Pérez-Herranz, V., & Zoppas-Ferreira, J. (2017). Influence of the co-ions on the transport of sulfate through anion exchange membranes. 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    Influence of the co-ions on the transport of sulfate through anion exchange membranes

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    [EN] The increasing demand for clean industrial processes has intensified the use of electrodialysis (ED) in the treatment of metal containing effluents from plating processes. Nickel rinsewater is a multicomponent solution that can be treated by ED in order to recover chemicals and reuse water. The investigation of the different phenomena involved in the transport of anions through anion-exchange membranes in this wastewater has been performed in different synthetic solutions by chronopotentiometry. Parameters like the limiting current density (i(lim)), the plateau length (Delta U-m), the resistance of the ohmic region (R-ohm) and the resistance of the overlimiting region (R-3) were also determined. Even though an anion exchange membrane (AEM), the limiting current density was affected by the proton leakage phenomena, indicated that the proton H+ has a greater effect than the other co-ions (Ni2+, Mg2+ and Na+). Ohmic resistances were reduced and plateau lengths were increased in the presence of protons. For salts solutions (without acid) the highest diffusion coefficients and lowest co-ion hydrated radii gave the highest plateau lengths and i(lim), but the lowest R-ohm.This study was financially supported by Erasmus Brazilian Windows Plus (EBW+), CAPES, CNPq, BNDES, FINEP, SCIT and FAPERGS.Benvenuti, T.; García Gabaldón, M.; Ortega Navarro, EM.; Rodrigues, M.; Bernardes, A.; Pérez-Herranz, V.; Zoppas-Ferreira, J. (2017). Influence of the co-ions on the transport of sulfate through anion exchange membranes. Journal of Membrane Science. 542:320-328. doi:10.1016/j.memsci.2017.08.021S32032854

    Unbounded violation of tripartite Bell inequalities

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    We prove that there are tripartite quantum states (constructed from random unitaries) that can lead to arbitrarily large violations of Bell inequalities for dichotomic observables. As a consequence these states can withstand an arbitrary amount of white noise before they admit a description within a local hidden variable model. This is in sharp contrast with the bipartite case, where all violations are bounded by Grothendieck's constant. We will discuss the possibility of determining the Hilbert space dimension from the obtained violation and comment on implications for communication complexity theory. Moreover, we show that the violation obtained from generalized GHZ states is always bounded so that, in contrast to many other contexts, GHZ states do in this case not lead to extremal quantum correlations. The results are based on tools from the theories of operator spaces and tensor norms which we exploit to prove the existence of bounded but not completely bounded trilinear forms from commutative C*-algebras.Comment: Substantial changes in the presentation to make the paper more accessible for a non-specialized reade

    OTELO survey: Deep BVRI broad-band photometry of the Groth strip

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    Context. The Groth field is one of the sky regions that will be targeted by the OTELO (OSIRIS Tunable Filter Emission Line Object) survey in the optical 820 nm and 920 nm atmospheric windows. A complementary broad-band photometric catalogue of the field is essential for several purposes, in particular the inequivocal identification of sources, photometric redshift estimation, and population synthesis fitting.Aims. We aim to describe the OTELO survey and present deep BVRI imaging data of the Groth field. Galaxy number counts, colour distributions and galaxy clustering are analysed.Methods. BVRI deep images (?8 ks) were obtained with the Prime Focus Camera at the WHT (La Palma) and reduced with the IRAF package. The extraction and photometry of the sources was done with SExtractor software. We analysed the final catalogue to obtain galaxy number counts, as well as galaxy correlation functions as a function of I magnitude and V - I colour. It is also compared with estimations from mock catalogues of the Virgo-Millenium consortium.Results. We find excellent agreement between observed and mock data number counts. We also find evidence of galaxy clustering evolution and strong dependence of the angular correlation function on the V - I observed colour. Our data favour a flattening of the clustering amplitude with median apparent magnitude. The good general agreement between our clustering analysis and the estimates from the mock data is remarkableAcknowledgements. This work was supported by the Spanish Plan Nacional de Astronomía y Astrofísica under grants AYA2005–04149 and AYA2006–2358. We thank the referee for helpful comments that improved the clarity of this paper. The Millennium Simulation databases used in this paper and the web application providing online access to them were constructed as part of the activities of the German Astrophysical Virtual Observatory. IRAF is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation. This publication makes use of data products from the Two Micron All Sky Survey, which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation

    Sulfuric acid recovery from acid mine drainage by means of electrodialysis

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    In the present work the recovery of sulfuric acid from acid mine drainage by means of 3-compartment electrodialysis (ED) is evaluated. An effective recovery of sulfuric acid free from Fe(III) species was obtained in the anodic compartment as a result of the co-ion exclusion mechanism in the membranes. The difference in the pH and pSO42 − values between the membrane phase and the external electrolyte promotes the dissociation of complex species inside the membranes. This phenomenon impedes the transport of Fe(III) and sulfates in the form of complex ions toward the anodic and cathodic compartment, respectively. The current efficiency values of the anion-exchange membrane at different current densities were approximately constant with time. However, the increase in the recovery of acid decreases as the current increases. This result is explained by the shift in the equilibrium at the membrane/solution interface as more SO42 − ions cross the anionic membrane and, by the enhancement of the dissociation of water when the limiting current density is exceeded. The main limitation of the process is related to an abrupt increase in the cell voltage due to the formation of precipitates at the surface of the cation-exchange membrane.This work was supported by Ministerio de Economia y Competitividad (Spain) with the project number CTQ2012-37450-C02-01/PPQ. M.C. Marti-Calatayud is grateful to the Universitat Politecnica de Valencia for a postgraduate grant (Ref.: 2010-12). D.C. Buzzi wants to express her gratitude to CAPES (Brazil) for a postgraduate grant (Proc. BEX 8747/11-3).Martí Calatayud, MC.; Cardoso Buzzi, D.; García Gabaldón, M.; Ortega Navarro, EM.; Bernardes, A.; Suarez Tenorio, JA.; Pérez Herranz, V. (2014). Sulfuric acid recovery from acid mine drainage by means of electrodialysis. Desalination. 343:120-127. https://doi.org/10.1016/j.desal.2013.11.03112012734

    Control biológico In Vitro de nematodos agalladores (Meloidogyne sp.) a base de quitosano y fluensulfone

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    El nematodo agallador (Meloidogyne sp.) tiene importancia económica potencial en diversos cultivos, en su combate casi siempre se han utilizado diferentes productos de agroquímicos, por lo que se necesita evaluar nuevos productos que sean una mejor alternativa en su manejo y en el cuidado al medio ambiente. En el presente trabajo se evaluó la eficacia biológica de diferentes extractos del quitosano un biopolímero natural con efecto nematicida y regulador de poblaciones de estos fitonematodos y Fluensulfone un nematicida de amplio espectro, el estudio se realizó In vitro, se colectaron muestras de suelo y se extrajeron los nematodos mediante el método de embudo de Baermann, se colocaron en cajas petri en diluciones con 30-35 nematodos por unidad experimental, en donde para su control se utilizó quitosano extraído de langostino de rio y quitosano comercial a diferentes concentraciones (0. 25, 0.50, 0.75), así mismo un nematicida comercial con extracto de quitosano Nematrol Plus , esto comparado con otros nematicidas comerciales Ditera (Myrothecium verrucaria  ),  Nemover  (Extracto  de  pino)  y  Nimitz  (Fluensulfone)  .Se  encontró  que  el  efecto nematicida del quitosano en dosis media (0.50) fue mejor posterior a las 24 horas después de la aplicación con una mortalidad de 95.83 a 100 % de nematodos,  y una eficacia del 100 %, esto comparado con los nematicidas comerciales

    The Absence of Caspase-8 in the Dopaminergic System Leads to Mild Autism-like Behavior

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    In the last decade, new non-apoptotic roles have been ascribed to apoptotic caspases. This family of proteins plays an important role in the sculpting of the brain in the early stages of development by eliminating excessive and nonfunctional synapses and extra cells. Consequently, impairments in this process can underlie many neurological and mental illnesses. This view is particularly relevant to dopamine because it plays a pleiotropic role in motor control, motivation, and reward processing. In this study, we analyze the effects of the elimination of caspase-8 (CASP8) on the development of catecholaminergic neurons using neurochemical, ultrastructural, and behavioral tests. To do this, we selectively delete the CASP8 gene in cells that express tyrosine hydroxylase with the help of recombination through the Cre-loxP system. Our results show that the number of dopaminergic neurons increases in the substantia nigra. In the striatum, the basal extracellular level of dopamine and potassium-evoked dopamine release decreased significantly in mice lacking CASP8, clearly showing the low dopamine functioning in tissues innervated by this neurotransmitter. This view is supported by electron microscopy analysis of striatal synapses. Interestingly, behavioral analysis demonstrates that mice lacking CASP8 show changes reminiscent of autism spectrum disorders (ASD). Our research reactivates the possible role of dopamine transmission in the pathogenesis of ASD and provides a mild model of autism

    Safety of switching from intravenous to subcutaneous rituximab during first-line treatment of patients with non-Hodgkin lymphoma: the Spanish population of the MabRella study

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    Rituximab is a standard treatment for non-Hodgkin diffuse large B-cell (DLBCL) and follicular (FL) lymphomas. A subcutaneous formulation was developed to improve the resource use of intravenous rituximab, with comparable efficacy and safety profiles except for increased administration-related reactions (ARRs). MabRella was a phase IIIb trial to assess the safety of switching from intravenous to subcutaneous administration of rituximab during first-line induction/maintenance for DLBCL or FL, focusing on ARRs. Efficacy, satisfaction and quality of life were also assessed. Patients received subcutaneous rituximab plus standard induction chemotherapy for DLBCL or FL for 4–7 cycles, and/or every 2 months maintenance monotherapy for FL for 6–12 cycles. The study included 140 patients: DLBCL, n = 29; FL, n = 111. Ninety-five percent of patients experienced adverse events, reaching grade ≥3 in 38 6% and were serious in 30 0%. AARs occurred in 48 6%, mostly (84 9%) at the injection site, with only 2 1% of patients reaching grade 3. The end-of-induction complete/unconfirmed complete response rate was 69 6%. After a median follow-up of 33 5 months, median disease-/event-/progression-free and overall survivals were not attained. The Rituximab Administration Satisfaction Questionnaire showed improvements in overall satisfaction and the EuroQoL-5D a good quality-of-life perception at induction/maintenance end. Therefore, switching to subcutaneous rituximab showed no new safety issues and maintained efficacy with improved satisfaction and quality of life

    Perrault syndrome with neurological features in a compound heterozygote for two TWNK mutations : Overlap of TWNK-related recessive disorders

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    Altres ajuts: This research was supported with cofounding from the European Regional Development Fund (ERDF), "A way to make Europe") (to IdC); S2017/BMD‑3721‑RAREGENOMICS‑CM from the Consejería de Educación e Investigación de la Comunidad de Madrid (to MAMP).Background: Perrault syndrome is a rare autosomal recessive disorder that is characterized by the association of sensorineural hearing impairment and ovarian dysgenesis in females, whereas males have only hearing impairment. In some cases, patients present with a diversity of neurological signs. To date, mutations in six genes are known to cause Perrault syndrome, but they do not explain all clinically-diagnosed cases. In addition, the number of reported cases and the spectra of mutations are still small to establish conclusive genotype-phenotype correlations. Methods: Affected siblings from family SH19, who presented with features that were suggestive of Perrault syndrome, were subjected to audiological, neurological and gynecological examination. The genetic study included genotyping and haplotype analysis for microsatellite markers close to the genes involved in Perrault syndrome, whole-exome sequencing, and Sanger sequencing of the coding region of the TWNK gene. Results: Three siblings from family SH19 shared similar clinical features: childhood-onset bilateral sensorineural hearing impairment, which progressed to profound deafness in the second decade of life; neurological signs (spinocerebellar ataxia, polyneuropathy), with onset in the fourth decade of life in the two females and at age 20 years in the male; gonadal dysfunction with early cessation of menses in the two females. The genetic study revealed two compound heterozygous pathogenic mutations in the TWNK gene in the three affected subjects: c.85C>T (p.Arg29∗), previously reported in a case of hepatocerebral syndrome; and a novel missense mutation, c.1886C>T (p.Ser629Phe). Mutations segregated in the family according to an autosomal recessive inheritance pattern. Conclusions: Our results further illustrate the utility of genetic testing as a tool to confirm a tentative clinical diagnosis of Perrault syndrome. Studies on genotype-phenotype correlation from the hitherto reported cases indicate that patients with Perrault syndrome caused by TWNK mutations will manifest neurological signs in adulthood. Molecular and clinical characterization of novel cases of recessive disorders caused by TWNK mutations is strongly needed to get further insight into the genotype-phenotype correlations of a phenotypic continuum encompassing Perrault syndrome, infantile-onset spinocerebellar ataxia, and hepatocerebral syndrome
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